Heated alcohol extraction of herbs

ABSTRACT

The present invention relates to methods for the extraction of herbs and plant materials. More particularly, the present invention relates to extraction methods for Echinacea. The extraction methods of the present invention provide a higher soluble solids content and a higher level of desired marker compounds, such as alkylamides, than conventional extraction procedures. Thus, the extraction methods of the present invention result in a greater yield at a lower cost from a given amount of starting material.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to novel methods for the extractionof herbs and plant materials. More particularly, the present inventionrelates to extraction methods for Echinacea. The extraction methods ofthe present invention provide a higher soluble solids content and ahigher level of desired marker compounds, such as alkylamides, thanconventional extraction procedures. Thus, the extraction methods of thepresent invention result in a greater yield at a lower cost from a givenamount of starting material.

[0002] Typical processes for the extraction of nutrients from herbs usewater or alcohol. In traditional processes, however, ambient temperaturewater or alcohol is generally used for the extraction. Typical processesinvolve taking the herb, milling it, and extracting the herb withalcohol and water at some strength of alcohol, generally 70% to 90%, fora few hours to extract soluble solids and nutrients.

[0003] Echinacea contains numerous active phytochemicals that haveimmunomodulatory and other beneficial activities. There is a longtradition of the use of Echinacea preparations in the adjuvant therapyof inflammations, skin damage, and, more typically, infections. TheEchinacea plant is a popular herbal immunostimulant. The ability ofEchinacea to stimulate the immune system in a nonspecific manner isexemplified in the enhancement of phagocytosis seen in cells treatedwith Echinacea (see, Sun et al., The American coneflower: a prophylacticrole involving nonspecific immunity, J. Altern. Complement Med., 5(5):437-446 (1999)). Echinacea's immunomodulatory activity has beenattributed to various actives, including alkylamides, phenolics,polysaccharides, alkaloids, glycoproteins, and flavonoids (see, Bauer,R. and Wagner, H., Echinacea species as potential immunostimulatorydrugs, in Economic and Medicinal Plant Research, Ch. 8, p.253, Wagner,H. and Farnsworth, N. R. (Editors), Academic Press Limited, New York,N.Y., (1991)).

[0004] It is, therefore, desirable to develop more efficient andcost-effective methods of extracting nutrients from herbs such asEchinacea.

SUMMARY

[0005] The present invention relates to novel methods for the extractionof herbs and plant materials. The extraction methods of the presentinvention result in greater yields at lower cost than conventionalextraction processes.

[0006] In one aspect, the present invention relates to extractionmethods that result in higher yields of soluble solids than conventionalextraction processes.

[0007] In another aspect, the present invention relates to extractionmethods that result in higher levels of marker compounds, such asalkylamides, than conventional extraction processes.

[0008] In another aspect, the present invention relates to extractionmethods that yield material with better tableting characteristics thanconventional extraction processes.

[0009] In another aspect, the present invention relates to extractionmethods that are lower in cost than conventional extraction processes.The methods of the present invention result in better quality yields andhigher yields from a given amount of starting material, therebydecreasing the cost of the final product.

BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS

[0010]FIG. 1 is a flow chart illustrating an herb extraction processaccording to the present invention.

[0011]FIG. 2 is a flow chart illustrating a preferred embodiment of anherb extraction process according to the present invention.

[0012]FIG. 3 is a flow chart illustrating one preferred embodiment of anEchinacea root extraction processing according to the present invention.

[0013]FIG. 4 is a graph illustrating the percent of soluble solids fromheated and unheated Echinacea purpurea extractions using a 10:1 alcoholto root ratio.

[0014]FIG. 5 is a graph illustrating the percent of soluble solids fromheated and unheated Echinacea angustifolia extractions using a 10:1alcohol to root ratio.

[0015]FIG. 6 is a graph illustrating moisture uptake of Echinaceapurpurea extractions using a 10:1 alcohol to root ratio.

[0016]FIG. 7 is a graph illustrating moisture uptake of Echinaceaangustifolia extractions using a 10:1 alcohol to root ratio.

DETAILED DESCRIPTION OF THE INVENTION

[0017] In accordance with the present invention, novel methods for theextraction of herbs and plant materials are provided. The extractionmethods of the present invention provide greater yields at lower coststhan conventional extraction processes. The novel extraction methods ofthe present invention yield a product with higher yields of solublesolids, higher levels of marker compounds, such as alkylamides, andbetter tableting characteristics than conventional extraction processes.

[0018] Although the experiments described herein use Echinaceaangustifolia and Echinacea purpurea, the contemplated scope of presentinvention is not limited to these two species, or to Echinacea speciesin general, but includes all species of herbs or plant materials.Presently preferred, however, are Echinacea angustifolia and Echinaceapurpurea which are used in the experiments described herein.

[0019] Experiments were carried out to determine optimal extractionconditions to yield maximum soluble solids. Maximizing soluble solids isimportant to keep the cost of extraction low while maintaining a highyield of dry extract.

[0020] The extraction process is generally illustrated in FIG. 1. Theextraction process can be used for any type of herb or plant material.Before starting the batch, all equipment used for processing is cleanedand sanitized. A sample of starting material (the dried herb root) iscollected for analysis. The raw starting material is weighed and addedto the extraction tank (12). An alcohol solution is fed into theextraction tank (12). The extraction tank (12) is heated and thecontents of the tank are preferably agitated during the extraction. Theextraction is carried out for about two hours, maintaining temperatureand agitation throughout. The percentage of soluble solids present ismonitored during the extraction, for example, by measuring therefractive index.

[0021] After the extraction, the contents of the extraction tank arepreferably cooled to ambient temperature by circulating cool waterthrough the jacket of the extraction tank. The non-soluble solids arethen separated from the liquid extract with a separation device (14).Separation can be carried out, for example, using a filtration device, acentrifuge, a screw press, or any other separation device. At thispoint, a sample of liquid extract may be collected for analysis ofdesired marker compounds.

[0022] The liquid extract is loaded into an evaporator (16), and thetemperature is raised in order to distill off the alcohol. Distillationis complete when the alcohol stops boiling off. This can be confirmed bymeasuring the percent of soluble solids in the concentrate. The targetfor soluble solids is about 9-11% after distillation is complete.

[0023] The liquid extract is then concentrated by evaporation to atarget level of soluble solids and transferred to covered containers.The target level of soluble solids depends on the end use of theproduct. The liquid extract is generally concentrated to a target levelfrom about 2 to 3% soluble solids to about 20 to 45% soluble solids inthe concentrate for applications where one spay dries, freeze dries,tray dries, or vacuum dries the concentrate to produce a powderedextract. The powdered extract can then be used as granules or used “asis” to make tablets, two-piece hard shell capsules, or other forms. Theliquid extract can also be concentrated from about 2 to 3% solublesolids to about 20 to 30% soluble solids and alcohol (grain or organic)can be added to make a spray-type product or a dropper-type product.

[0024] Using Echinacea, a series of experiments were conducted todetermine the optimal conditions for the extraction process. Alcoholconcentrations between 50% and 90% alcohol were tested. An alcoholconcentration of about 70% was found to be optimal. Lower alcoholconcentrations yield a lower levels of soluble solids. Higher alcoholconcentrations of about 85% to 90% can yield a higher level ofalkylamides, but the yield of other important phytochemicals, such aspolysaccharides are reduced. Additionally, using the higher alcoholconcentrations greatly increases the cost of the extraction process andmay therefore be cost prohibitive.

[0025] Various extraction temperatures ranging from ambient temperature(approximately 18° C. to 24° C.) to about 70° C. were tested. The yieldof soluble solids from the extraction generally increases withincreasing extraction temperature. As the extraction temperature reachesabout 65° C. to 70° C., nearing the boiling point of alcohol, there areincreased emissions from the heated alcohol. The extraction temperatureof about 60° C. was found to be optimal.

[0026] The extraction time was also tested. As seen in Table 1 and Table2, the yield of soluble solids generally peaks at about 105-120 minutesof extraction. Many experiments were carried out with longer extractiontimes, but extraction times of up to about 6.3 hours have a shownsimilar mass of soluble solids and similar alkylamides yields as the2-hour extraction. Longer extraction times yield diminishing returns andsignificantly increase the cost of the extraction, as found inexperiments conducted with extraction times up to about six hours.Therefore, an extraction time of about 2 hours is considered optimal.

[0027] A preferred embodiment of the extraction process for Echinacea isillustrated in FIG. 2 and FIG. 3. A manufacturing batch size wouldcontain, for example, 400 Kg Echinacea and 4000 Kg ethanol (1260gallons). Before starting the batch, all equipment used for processingis cleaned and sanitized. One (1) Kg of starting material is collectedfor analysis. The starting material is stored in an herb storage tank(24). The raw starting material is weighed and added to the extractiontank (26). An ethanol/water mixture is made of about 70% ethanol and 30%water in a quantity sufficient to give a 1:10 ratio (weight: weight) ofraw herb material to solvent. The ethanol/water mixture is stored in analcohol storage tank (22). The alcohol is then fed into the extractiontank (26). The extraction tank (26) is heated to 60° C./140° F., and thecontents of the extraction tank (26) are agitated during the extraction.The extraction is carried out for about two hours after reaching 60°C./140° F., maintaining temperature and agitation throughout. Thepercentage of soluble solids present is monitored during the extraction.Soluble solids can be measured, for example, by measuring the refractiveindex of the extract with a refractometer or through a loss on drying(LOD) technique.

[0028] After the extraction is complete, the contents of the tank arepreferably cooled to ambient temperature by circulating cool water inthe jacket of the extraction vessel. The slurry from the tank is thenpumped out to separate the non-soluble solids from the liquid extractusing a separation device (14). Separation can be carried out, forexample, using a filtration device, a centrifuge, a screw press, or anyother separation device. In one preferred embodiment, a shaker screen(28) and a screw press (30) are used to separate the liquid extract fromthe solids (referred to as cake or marc). At this point, a 100 ml sampleof liquid extract may be collected for analysis of alkylamides.

[0029] The liquid extract from both the shaker screen (28) and the screwpress (30) are transferred to a storage tank (38). From the storage tank(38), the liquid extract is loaded into an evaporator (40), and thetemperature is brought to about 77° C.(170° F.), to distill off thealcohol. Distillation is complete when the alcohol stops boiling off.This can be confirmed by measuring the percent of soluble solids in theconcentrate. The target for soluble solids is about 9-11% afterdistillation is complete. A 100 ml sample of the liquid concentrate iscollected for analysis of alkylamides.

[0030] The liquid extract is then concentrated through evaporation. Theevaporation is carried out in an evaporator (40) to a target of about25%±2% soluble solids. The level of soluble solids is monitored using arefractometer every 30 minutes until the target is achieved. Dependingon the desired end product, the liquid extract is then optionallyfiltered through a filter (42) to remove remaining insoluble solids. Forexample, if the end product is a liquid (for dropper or spray-typeproduct), it is desirable to filter off any insoluble solids. For aliquid product, the extract is preferably filtered through a filter witha minimum of at least about a 200 mesh. This removes particulate matterthat could otherwise interfere with the delivery of the liquid productby, for example, clogging a spray bottle. Alternatively, if the endproduct is a solid powder, it is not necessary to remove remaininginsoluble solids.

[0031] At this point, the concentrated liquid extract is frozen andstored if it is not to be further processed with 24 hours. As processingcontinues, the concentrated liquid extract is then pasteurized in apasteurizer (46) at 240° F. for two minutes to kill any bacteria thatmay be present in the extract. From the pasteurizer (46), the extract isfurther processed for a liquid end product or a powder end product. Fora liquid end product, the extract is transferred to a liquid productcontainer (48) and organic alcohol is added to produce a liquidEchinacea product.

[0032] Alternatively, if a dry product is desired, the extract istransferred to a spray dryer (50). Maltodextrin is added in an amountequal to 50% of the mass of the soluble solids present in the liquidconcentrate, and the product is spray dried. The spray-dried powder canthen be blended with other ingredients and/or formed into tablets forthe final product.

[0033] In one preferred embodiment, the extraction process includes asolvent recovery system. After the initial extraction, the non-solublesolids are separated from the liquid extract using a separation device(14, FIG. 1) (28 and 30, FIG. 2). After separation, the non-solublesolids are transferred to a solvent recovery unit (32) in which thealcohol solvent is dried off of the non-soluble solids. The non-solublesolids are separated and discharged appropriately. The recovered solventis stored in a reclaimed alcohol tank (36). The recovered alcohol canthen be reused in subsequent extractions. The solvent recovery systemincreases the efficiency and reduces the cost of extraction. It ispossible to recover up to 95% of the alcohol used in the extraction.Additionally, by removing the alcohol from the dried cake or marc (thenon-soluble solids), the solids can be more easily disposed of.

[0034] In another series of experiments, four alcohol extractionprocesses were carried out using the roots of each of two Echinaceaspecies: Echinacea purpurea and Echinacea angustifolia. The raw materialwas Trout Lake Farm tea-cut in all cases. The two variables for eachroot extraction process were (1) the alcohol to root ratio (by weight),and (2) the temperature at which the extraction was carried out. The twoalcohol to root ratios used were (a) 10:1 and (b) 7:1. The twotemperatures used were (a) unheated, or ambient temperature(approximately 65° F. to 75° F., or 18° C. to 24° C.) and (b) heated, orapproximately 60° C./140° F. For each extraction, the process includedextraction, concentration, and spray drying.

[0035] Unexpected and surprising results were found with the extractionusing heated alcohol at a 10:1 alcohol to root ratio in the case of bothEchinacea purpurea and Echinacea angustifolia roots. The heatedextractions using a 10:1 alcohol to root ratio generally produced 40% to50% more soluble solids, concentrated well, and spray dried (withM510-Maltodextrin) at a higher efficiency to produce a better spraydried powder (one that was non-sticking and had lower moisture uptake)compared to the unheated extractions.

[0036] Table 1 and FIG. 4 show the percent of soluble solids present inboth heated and unheated Echinacea purpurea extractions using a 10:1alcohol to root ratio. Table 2 and FIG. 5 show the percent of solublesolids present in both heated and unheated Echinacea angustifoliaextractions using a 10:1 alcohol to root ratio. The heated extractionsyield higher levels of soluble solids throughout the course of theextraction. TABLE 1 Percent soluble solids from heated and unheatedEchinacea purpurea extractions using a 10:1 alcohol to root ratio 15min. 30 min. 60 min. 90 min. 105 min. 120 min. 150 min. Unheated 0.37%0.73% 0.89% 1.10% 1.45% 1.29% 1.28% Heated 0.70% 0.85% 1.35% 1.90% 1.86%1.86% 1.75%

[0037] TABLE 2 Percent soluble solids from heated and unheated Echinaceaangustifolia extractions using a 10:1 alcohol to root ratio 15 min. 30min. 60 min. 90 min. 105 min. 120 min. 150 min. Unheated 0.80% 0.95%1.12% 1.20% 1.78% 1.70% 1.65% Heated 1.14% 2.35% 2.60% 2.40% 2.49% 2.34%2.30%

[0038] Powder characteristics were compared for each of the four extractsamples (Echinacea purpurea, heated and unheated, and Echinaceaangustifolia , heated and unheated). All of the samples have “no flow.”No flow is a measure of the stickiness or flowability of a material, andcan be measured by the rate at which a material flows through a cone orfunnel. For tableting, no flow is a characteristic that is notpreferred. The samples with the best powder characteristics, however,were the powders made with the heated alcohol extraction process.

[0039] Table 3 shows the results for moisture uptake for spray-driedextracts of Echinacea purpurea and Echinacea angustifolia prepared byboth the heated and unheated extraction methods. FIG. 6 illustrates theresults for moisture uptake for spray dried extracts of Echinaceapurpurea prepared using a 10:1 alcohol to root ratio. FIG. 7 illustratesthe results for moisture uptake for spray dried extracts of Echinaceaangustifolia prepared using a 10:1 alcohol to root ratio. TABLE 3Moisture Uptake of Echinacea purpurea and Echinacea angustifoliaextractions. Time in Minutes 0 60 90 150 270 390 min. min. min. min.min. min. E. purpurea 0 3.29% 5.65% 7.01% 8.44% 9.28% 1:10, unheated E.purpurea 0  2.6% 5.04% 6.15%  8.2% 9.14% 1:10, heated E. angustifolia 03.35% 5.29% 6.62% 8.62% 9.73% 1:10, unheated E. angustifolia 0 3.11% 4.8%  6.2% 8.01% 9.02% 1:10, heated E. purpurea 0 2.73% 5.68% 6.44%8.55% 9.55% 1:7, unheated E. purpurea 0 4.06% 5.1% 5.26% 6.15%  6.7%1:7, heated E. angustifolia 0  3.3% 5.47% 6.34% 7.61% 8.28% 1:7,unheated E. angustifolia 0 1.87%  3.7% 5.15% 7.32%  8.6% 1:7, heated

[0040] Moisture uptake is measured as the percent increase in weight ofthe spray-dried powder over time. As illustrated in Table 3, thespray-dried powder from the heated extractions absorbs less moisturethan that of the unheated extractions. For example, spray-dried powderextract of Echinacea purpurea root, prepared using a 10:1 alcohol toroot ratio, showed moisture uptake of 3.29 percent after 60 minutes fromthe unheated extraction, but only 2.6 percent after 60 minutes from theheated extraction. The moisture uptake data at 60 minutes is ofparticular interest because that is the approximate length of timeduring which the powder extract is exposed to air before tableting. Theless moisture absorbed by the extract, the better the tabletingcharacteristics of the powder.

[0041] In contrast, material extracted with unheated alcohol did nothave any flow, was lumpy, and had a high moisture uptake. This materialcould not be tableted. (See Table 4, Column L). Material extracted withunheated alcohol had a very high ratio of raw material to dry extract.In other words, with the unheated alcohol extraction, much more startingmaterial was required to yield a given amount of dry extract product(See Table 4, Column K).

[0042] Alkylamides, which are used as a marker compounds, are generallypresent in commercially available Echinacea at a level of about 0.5%alkylamides for Echinacea angustifolia , and about 0.1% for Echinaceapurpurea . Using the extraction methods of the present invention,Echinacea angustifolia extracts have a level of alkylamides between 0.5%to 2.4%, with an average of 0.95%, and Echinacea purpurea extracts havea level of alkylamides between 0.136% to 0.534%, with an average of0.25%. The extraction methods of the present invention, therefore yielda higher level of desired marker compounds.

[0043] The following examples describe extractions of Echinacea purpureaand Echinacea angustifolia according to the methods of the presentinvention. The results from these examples is summarized in Table 4.

EXAMPLE 1

[0044]Echinacea purpurea root

[0045] Alcohol to root ratio: 10:1

[0046] Temperature: unheated (ambient)

[0047] (Table 4, line 1).

[0048] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 10:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was unheated. The 50 kgs of root wereintroduced into the tank through the manhole. Once the raw material wasbatched into the tank with 70% EtOH/30% H₂O, a 2-hour extraction wasstarted. Samples were taken at 15-minute intervals to check solublesolids level.

[0049] Mass Balance: 50 kgs+391 kgs ethanol (200 proof)+150 kgsH₂O=493.5 kgs of liquid extract+97.5 kgs Cake (1.29% solids) (60% to 65%moisture)

[0050] The solids were separated from the liquid in a decantercentrifuge and the liquid screened with an 80-mesh screen. Liquidextract was concentrated in an evaporator to obtain 29.60 kgs at 21.50%solids. The concentrate was checked for solids. Maltodextrin (M510) wasthen added in an amount equal to 50% of the solids level in theconcentrate. For example, 29.60 kg concentrate×21.50% solids=6.36 kgsolids. 6.36 kg solids×50%=3.18 kg maltodextrin added. (See Table 4,line 1) The pH was 4.7. The concentrate was spray dried in a spray dryerto yield only 56.04% powder. ([5.35 kg after spray drying/(6.36 kg totalsolids+3.18 kg carrier)]×100=56%). The powder was very sticky, did notflow at all, and yielded only 5.35 kgs. The ratio of root to spray driedpowder was 9.35:1.

EXAMPLE 2

[0051]Echinacea purpurea root

[0052] Alcohol to root ratio: 10:1

[0053] Temperature: heated (60° C./140° F.)

[0054] (See Table 4, line 2).

[0055] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 10:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was heated to 60° C. before the 50 kgsof root were introduced. The 50 kgs of root were introduced into thetank through the manhole. Once the raw material was batched into thetank with 70% EtOH/30% H₂O, a 2-hour extraction was started afterreaching the desired temperature of 60° C. Samples were taken at15-minute intervals to check soluble solids level.

[0056] Mass Balance: 50 kgs+391 kgs ethanol (200 proof)+150 kgsH₂O=518.2 kgs extract+73.1 kgs Cake (1.86% solids) (58% to 60% moisture)

[0057] The solids were separated from the liquid in a decantercentrifuge and the liquid screened through an 80-mesh screen. Liquidextract was concentrated in an evaporator to obtain 42 kgs at 23%solids. The concentrate was checked for solids, and maltodextrin (M510)was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 5.1. The concentrate was spray dried to yield76.05%.

EXAMPLE 3

[0058]Echinacea angustifolia root

[0059] Alcohol to root ratio: 10:1

[0060] Temperature: unheated (ambient)

[0061] (See Table 4, line 3)

[0062] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 10:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was unheated. The 50 kgs of root wereintroduced into the tank through the manhole. Once the raw material wasbatched into the tank with 70% EtOH/30% H₂O, a 2-hour extraction wasstarted. Samples were taken at 15-minute intervals to check solublesolids level.

[0063] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=492.9 kgs of Extract+98.1 kgs of Cake (1.78% soluble solids) (63to 65% moisture)

[0064] The solids were separated from the liquid in a decantercentrifuge and the liquid screened through an 80-mesh screen. Liquidextract was concentrated in an evaporator to obtain 49 kgs at 18%solids. The concentrate was checked for solids, and maltodextrin (M510)was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 4.7. The concentrate was spray dried to yield81.03%.

EXAMPLE 4

[0065]Echinacea angustifolia root

[0066] Alcohol to root ratio: 10:1

[0067] Temperature: heated (60° C./140° F.)

[0068] (See Table 4, line 4)

[0069] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 10:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was heated to 60° C. before the 50 kgsof root were introduced. The 50 kgs of root were introduced into thetank through the manhole. Once the raw material was batched into thetank with 70% EtOH/30% H₂O, a 2-hour extraction was started afterreaching the desired temperature of 60° C. Samples were taken at15-minute intervals to check soluble solids level.

[0070] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=520.8 kgs of Extract+70.2 kgs of Cake (2.40% soluble solids) (56to 60% moisture)

[0071] The solids were separated from the liquid in a decantercentrifuge and the liquid was screened through an 80-mesh screen. Liquidextract was concentrated in an evaporator to obtain 48.5 kgs at 26%solids. The concentrate was checked for solids, and maltodextrin (M510)was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 5.1. The concentrate was spray dried to yield89.00%.

EXAMPLE 5

[0072]Echinacea purpurea root

[0073] Alcohol to root ratio: 7:1

[0074] Temperature: unheated (ambient)

[0075] (See Table 4, line 5)

[0076] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 7:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was unheated. The 50 kgs of root wereintroduced into the tank through the manhole. Once the raw material wasbatched into the tank with 70% EtOH/30% H₂O, a 2-hour extraction wasstarted. Samples were taken at 15-minute intervals to check solublesolids level.

[0077] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=493.0 kgs of Extract+98.0 kgs of Cake (1.21% soluble solids) (60to 65% moisture)

[0078] The solids were separated from the liquid in a decantercentrifuge, and the liquid was screened through an 80-mesh screen.Liquid extract was concentrated in an evaporator to obtain 26.0 kgs at23% solids. The concentrate was checked for solids, and maltodextrin(M510) was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 4.7. The concentrate was spray dried to yield66.50% .

EXAMPLE 6

[0079]Echinacea purpurea root

[0080] Alcohol to root ratio: 7:1

[0081] Temperature: heated (60° C./140° F.)

[0082] (See Table 8, line 6)

[0083] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 7:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was heated to 60° C. before the 50 kgsof root were introduced. The 50 kgs of root were introduced into thetank through the manhole. Once the raw material was batched into thetank with 70% EtOH/30% H₂O, a 2-hour extraction was started afterreaching the desired temperature of 60° C. Samples were taken at15-minute intervals to check soluble solids level.

[0084] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=509.0 kgs of Extract+82.0 kgs of Cake (1.25% soluble solids) (58to 60% moisture)

[0085] The solids were separated from the liquid in a decantercentrifuge and the liquid was screened through an 80-mesh screen. Liquidextract was concentrated in an evaporator to obtain 27.76 kgs at 23%solids. The concentrate was checked for solids, and maltodextrin (M510)was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 5.1. The concentrate was spray dried to yield84.44% .

EXAMPLE 7

[0086]Echinacea angustifolia root

[0087] Alcohol to root ratio: 7:1

[0088] Temperature: unheated (ambient)

[0089] (See Table 4, line 7)

[0090] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 7:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was unheated. The 50 kgs of root wereintroduced into the tank through the manhole. Once the raw material wasbatched into the tank with 70% EtOH/30% H₂O, a 2-hour extraction wasstarted. Samples were taken at 15-minute intervals to check solublesolids level.

[0091] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=489.0 kgs of Extract+102.0 kgs of Cake (1.076% soluble solids) (64to 66% moisture)

[0092] The solids were separated from the liquid in a decantercentrifuge, and the liquid was screened through an 80-mesh screen.Liquid extract was concentrated in an evaporator to obtain 22.80 kgs at23% solids. The concentrate was checked for solids, and maltodextrin(M510) was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 4.7. The concentrate was spray dried to yield51.05% . The material was of poor quality. It was light and fluffy, andalso stuck to the spray dryer.

EXAMPLE 8

[0093]Echinacea angustifolia root

[0094] Alcohol to root ratio: 7:1

[0095] Temperature: heated (60° C./140° F.)

[0096] (See Table 4, line 8)

[0097] Batches of 50 kg of root (tea cut) were used. The alcohol to rootratio was 7:1, and the concentration of the alcohol used was 70% (70%EtOH and 30% water). The alcohol was heated to 60° C. before the 50 kgsof root were introduced. The 50 kgs of root were introduced into thetank through the manhole. Once the raw material was batched into thetank with 70% EtOH/30% H₂O, a 2-hour extraction was started afterreaching the desired temperature of 60° C. Samples were taken at15-minute intervals to check soluble solids level.

[0098] Mass Balance: 50 kgs+391 kgs Ethanol (200 proof)+150 KgsWater=519.0 kgs of Extract+72.0 kgs of Cake (2.3% soluble solids) (58 to60% moisture)

[0099] The solids were separated from the liquid in a decantercentrifuge, and the liquid was screened through an 80-mesh screen.Liquid extract was concentrated in an evaporator to obtain 53.00 kgs at22.5% solids. The concentrate was checked for solids, and maltodextrin(M510) was added in an amount equal to 50% of the solids level in theconcentrate. The pH was 5.1. The concentrate was spray dried to yield87.77% .

[0100] The results from Examples 1-8 are shown in Table 4 in lines 1-8,respectively. TABLE 4 B C D Alcohol Extraction Kgs after E F G H I A toRoot Temp- Con- % Solids in Kgs Solids in Solids Ratio Kgs of Kgs afterJ Example Herb Ratio erature centration Concentrate ConcentrateHeated/Unheated Carrier Spray drying % Yield Number A B C D E F G H I J1 E. purpurea 10:1 Ambient 29.60 21.50 6.36 1.00 3.18 5.35 56.1% 2 E.purpurea 10:1 60 C./140 F. 42.00 23.00 9.66 1.52 4.83 11.02 76.0% 3 E.angustifolia 10:1 Ambient 49.00 18.00 8.82 1.00 4.41 10.72 81.0% 4 E.angustifolia 10:1 60 C./140 F. 48.50 26.00 12.61 1.43 6.31 16.83 89.0% 5E. purpurea  7:1 Ambient 26.00 23.00 5.98 1.00 2.99 5.965 66.5% 6 E.purpurea  7:1 60 C./140 F. 27.76 23.00 6.38 1.07 3.19 8.087 84.4% 7 E.angustifolia  7:1 Ambient 22.88 23.00 5.26 1.00 2.63 4.03 51.1% 8 E.angustifolia  7:1 60 C./140 F. 53.00 22.50 11.93 2.27 5.96 15.70 87.8%

[0101] Table 4 is shows yields for the various Echinacea extractionsdescribed in examples 1-8.

[0102] The Column labeled “Example Number” numbers the rows in the tableto correspond with the example numbers in the specification. Forexample, row 1 corresponds to Example 1. Column A, labeled “Herb,”indicates which herb was used in the extraction, Echinacea purpurea orEchinacea angustifolia.

[0103] Column B, labeled “Alcohol to Root Ratio,” indicates the alcoholto ratio use in the extraction, either 10:1 or 7:1.

[0104] Column C, labeled “Extraction Temperature,” indicates thetemperature at which the extraction was carried out, either ambienttemperature or 60 C./140 F.

[0105] Column D, labeled “Kgs after Concentration,” indicates the totalmass of the concentrated liquid extract.

[0106] Column E, labeled “% Solids in Concentrate,” indicates thepercentage of soluble solids present in the concentrated liquid extract.The percentage of soluble solids is determined by measuring therefractive index of the concentrated liquid extract.

[0107] Column F, labeled “Kgs Solids in Concentrate,” indicates the massof soluble solids in the concentrated liquid extract. The mass of thesoluble solids is calculated by multiplying the “Kgs afterConcentration” from Column D by the “% Solids in Concentrate” fromColumn E, and dividing by 100. For example, in row 1, (29.60 Kgs ofextract)(21.50% solids)/100=6.36 Kgs solids.

[0108] Column G, labeled “Solids Ratio Heated/Unheated,” indicates theratio of “Kgs Solids in Concentrate” from Column F for each pair ofexamples (pairs are 1 and 2; 3 and 4; 5 and 6; 7 and 8) comparing theheated extraction to the unheated extraction. In each case, the “KgsSolids in Concentrate” for the unheated or ambient extraction is set atone (1). In other words, the “Kgs Solids in Concentrate” for eachunheated extraction divided by itself equals one (1). The “Solids RatioHeated/Unheated” for the heated extraction is calculated by dividing the“Kgs Solids in Concentrate” for the heated extraction by the “Kgs Solidsin Concentrate” for the unheated extraction in the same pair to producea ratio. For example, in row 2, (9.66 Kgs Solids in Concentrate (HeatedExtract Example 2))/(6.36 Kgs Solids in Concentrate (Unheated ExtractExample 1))=1.52.

[0109] Column H, labeled “Kgs Carrier,” indicates the mass of thecarrier, in this case, Maltodextrin, that is added to the extract priorto spray drying. Maltodextrin (M510) is added in an amount equal to 50%of the solids level in the concentrate. The amount of carrier added iscalculated by dividing the “Kgs Solids in Concentrate” from Column F bytwo (2). For example, in row 1, the “Kgs Solids in Concentrate” fromColumn F is 6.36 Kgs. (6.36 Kgs Solids in Concentrate)/2=3.18 Kgs. Inthis example, Maltodextrin is added in an amount equal to half of thelevel of solids, or 3.18 Kgs Maltodextrin is added.

[0110] Column I, labeled “Kgs after Spray Drying,” indicates the yieldedmass in Kgs of the solids after spray drying. The mass after spraydrying includes the mass of the soluble solids and the mass of carrieradded before spray drying.

[0111] Column J, labeled “% Yield,” indicates the percentage of solublesolids yielded relative to the total mass of solids after spray drying.The “% Yield” is calculated by dividing the “Kgs after Spray Drying”from Column I by the sum of “Kgs Solids in Concentrate” from Column Fand “Kgs Carrier” from Column H. The result is then multiplied by 100 togive a percentage. For example, in row 1, [(5.35 Kgs after spraydrying)/(6.36 Kgs solids in concentrate)+(3.18 Kgs carrier)]×100=56.1%.

[0112] Column K, labeled “Kgs Herb for 1 Kg Powder,” indicates the massof the raw herb starting material required to yield 1 Kg of the extractpowder. “Kgs Herb for 1 Kg Powder” is calculated by dividing the mass ofthe raw starting material, by the “Kgs after Spray Drying” from ColumnI. The mass of the raw starting material is 50 Kgs for each of theexamples, 1-8. For example, in row 1, (50 Kgs starting material)/(5.35Kgs after spray drying)=9.34 Kg root to make 1 Kg extract.

[0113] Column L, labeled “Powder Evaluation,” relates to the evaluationof the spray dried powder in terms of its moisture uptake and flowcharacteristics. The two entries for Column L are “A” and “B.” “A”indicates that the powder had better tableting characteristics and lowermoisture uptake. “B” indicates that the powder does not flow well.

[0114] Column M, labeled “% Alkylamides,” indicates the percentage ofthe alkylamide marker compounds in each of the spray dried powders.

[0115] As illustrated by comparing the pairs of numbers in Column G, foreach pair of extractions, the heated alcohol extraction yielded moresoluble solids than the unheated extraction. As shown in Column J, thepercent yield was also higher for each heated extract compared to itsunheated pair. Consequently, as illustrated in Column K, for each pair,significantly less raw herb root is required to produce a given amountof spray dried extract for the heated extractions compared to theunheated extractions.

[0116] The experiments above show that by using a heated alcoholextraction process with a 10:1 alcohol to root ratio according to thepresent invention, the extraction yields up to 50% more soluble solidsand high levels of nutrients or marker compounds than conventionalextraction methods.

[0117] By using the methods of the present invention, there is a greateryield of powder when the alcohol/water solvent mixture is evaporated offthe liquid extract. A greater yield from a given amount of startingmaterial means that the process is economically more efficient thantraditional ambient temperature alcohol/water extractions. In bothcases, using Echinacea purpurea and Echinacea angustifolia, the productnot only was produced more efficiently and at a lower cost, but alsowith a higher level of the marker compounds, alkylamides.

[0118] In summary, there are numerous advantages to using the extractionmethods of the present invention. These extraction methods produced 40%to 50% more soluble solids, concentrated well, and spray dried (withM510-Maltodextrin) at a higher efficiency to produce a better(non-sticking, low moisture uptake) spray dried powder.

[0119] Although the description above contains many specifics, theseshould not be construed as limiting the scope of the invention, but asmerely providing illustrations of some of the presently preferredembodiments of this invention. Thus the scope of this invention shouldbe determined by the appended claims and their legal equivalents, ratherthan by the examples given.

What is claimed:
 1. A method of producing a plant extract comprising: a)providing plant material; b) contacting the plant material with analcohol solution to form a mixture, the alcohol solution comprisingabout 70% alcohol and about 30% water by weight, and being used in anamount sufficient to yield a ratio of about 1:10 by weight of plantmaterial to alcohol; c) heating the mixture to at least about 60° C.; d)maintaining the temperature of the mixture at for at least about 2hours, thereby yielding a liquid extract and non-soluble solids.
 2. Themethod of claim 1 further comprising: a) separating the non-solublesolids from the liquid extract; b) distilling at least a portion of thealcohol off of the liquid extract by raising the temperature of theliquid extract to a temperature above the boiling point of the alcohol.3. The method of claim 1 further comprising agitating the mixture instep d.
 4. The method of claim 1 wherein the alcohol is ethanol.
 5. Themethod of claim 1 wherein the plant material is Echinacea.
 6. The methodof claim 2 further comprising filtering the liquid extract.
 7. Themethod of claim 6 wherein the filter has a mesh of about 200 mesh orgreater.
 8. A plant extract having a high level of desired markercompounds, produced by a high temperature extraction process, comprisingthe following steps: a) providing plant material; b) contacting theplant material with an alcohol solution to form a mixture, the alcoholsolution comprising about 70% alcohol and about 30% water by weight, andbeing used in an amount sufficient to yield a ratio of about 1:10 byweight of plant material to alcohol; c) heating the mixture to about 60°C.; d) maintaining the temperature of the mixture at about 60° C. for atleast about 2 hours, thereby yielding a liquid extract and non-solublesolids.
 9. A method of producing a plant extract comprising: a)providing plant material; b) contacting the plant material with analcohol solution to form a mixture, the alcohol solution being used inan amount sufficient to yield a predetermined ratio of plant material toalcohol; c) heating the mixture to between about 50° C. and about 65°C.; d) maintaining the temperature of the mixture for between about 90and about 120 minutes, thereby yielding a liquid extract and non-solublesolids.
 10. The method of claim 7 wherein the alcohol solution isbetween about 50% to about 90% ethanol.
 11. The method of claim 7wherein the alcohol solution is between about 60% to about 80% ethanol.12. The method of claim 7 wherein the alcohol solution is between about65% to about 75% ethanol.
 13. The method of claim 7 wherein the alcoholsolution is 70% ethanol.
 14. The method of claim 7 wherein the ratio ofplant material to alcohol is between about 1:7 and about 1:10 by weight.15. The method of claim 7 wherein the ratio of plant material to alcoholis about 1:10 by weight.
 16. The method of claim 1 further comprising:a) separating the non-soluble solids from the liquid extract; b)distilling at least a portion of the alcohol off of the non-solublesolids and recovering the distilled alcohol.
 17. A method of producing atablet that contains a plant extract comprising: a) providing plantmaterial; b) contacting the plant material with an alcohol solution toform a mixture, the alcohol solution comprising about 70% alcohol andabout 30% water by weight, and being used in an amount sufficient toyield a ratio of about 1:10 by weight of plant material to alcohol; c)heating the mixture to between about 50° C. and about 65° C.; d)maintaining the temperature of the mixture for between about 90 andabout 120 minutes, thereby yielding a liquid extract and non-solublesolids. e) separating the non-soluble solids from the liquid extract; f)drying the liquid extract to form a powder extract; and g) directlycompressing the powder extract with other excipients to form a tablet.